Abstract
Phytoplankton play a crucial role in marine ecosystems due to their position at the base of the food web. As atmospheric CO2 levels continue to rise, the resulting increase in dissolved CO2 and the concurrent decrease in ocean pH will progressively impact phytoplankton communities. However, the response to elevated CO2 can vary significantly among phytoplankton groups and in tandem with existing, or altered, environmental conditions (e.g. light, temperature, nutrient availability). To address these variations, we conducted experiments in a controlled photobioreactor system, maintaining high and low light, constant temperature, sufficient nutrient levels, and two pCO2 concentrations for two regionally relevant phytoplankton in the northern Gulf of Mexico: Skeletonema sp. (a diatom) and Micromonas commoda (a green alga). Skeletonema sp. increased growth rates in the high light and high carbon treatments, but particulate organic carbon and nitrogen (POC/N) only responded to changes in light. M. commoda showed changes in growth rate and POC/N due to increased light and likely allocated more energy towards photosynthesis during elevated CO2 conditions. Skeletonema sp. displayed a decoupling between growth rate and silicification, leading to higher biogenic silica content per cell in elevated pCO2 environments, contrary to prior results for different diatom genera. These results highlight the necessity for genera-specific and regionally focused research, as the physiological plasticity among phytoplankton in response to regional conditions can vary.
Purpose
This dataset was generated to examine how elevated pCO2 and light conditions influence the growth and elemental composition of two phytoplankton species from the northern Gulf of Mexico. It provides controlled experimental measurements of physiological responses under varying pCO2 and light regimes via photobioreactor with eight culture tubes.
DOI: 10.57778/1t2g-aa42
Suggested Citation
Siersma, A., Dalessandri, S., Hoadley, K., Robertson, A., & Krause, J. (2026). Phytoplankton Responses to Changing Irradiance and Carbon Fertilization [Dataset]. dauphin. https://doi.org/10.57778/1T2G-AA42
Related Publication Citation
Attribution
This project was paid for [in part] with federal funding for the Alabama Center of Excellence from the Department of the Treasury under the Resources and Ecosystems Sustainability, Tourist Opportunities, and Revived Economies of the Gulf Coast States Act of 2012 (RESTORE Act) in cooperation with the State of Alabama Department of Conservation and Natural Resources under the Alabama Center of Excellence Program at the MESC/Dauphin Island Sea Lab.
